2. Endocrine glands: Secrete into blood flowing through them, to let the secretion function at distant parts of the body from the gland. They are ductless glands. Their secretions are called as hormones.

All the glands are located in distinct locations in the human body. They regulate the physiology to a large extent by receiving stimulus from the brain. So we can notice that those glands present in the brain secrete hormones which go outside the brain and act on other glands distributed in different parts of the body. They travel through the blood to the target organs after being released.